SELinux policycoreutils allows local users to execute arbitrary commands outside of the sandbox via a crafted TIOCSTI ioctl call.
https://marc.info/?l=selinux&m=147465160112766&w=2
https://github.com/SELinuxProject/selinux/commit/acca96a135a4d2a028ba9b636886af99c0915379
http://www.securitytracker.com/id/1037283
http://www.securityfocus.com/bid/93156
http://www.openwall.com/lists/oss-security/2016/09/25/1
http://rhn.redhat.com/errata/RHSA-2017-0536.html